The application value of low-dose of high-pitch scan mode of dual-source computed tomography in the chest of children

Objective To evaluate the radiation dose and image quality of the application of high-pitch scan mode of dualsource computed tomography in the chest of children.Methods 80 sick children who were going to do chest CT examination by dual-source CT system were randomly divided into two groups of A B.40 children of group A were examined with a in highpitch scan mode(pitch=3.0);40patients of group B were examined with in conventional pitch mode(pitch=1.2).The image quality,radiation dose(CTDIvol,DLP)and scaning time between the two groups were analysed.Results The Image quality of group A and B meet the requirements of the clinical diagnosis.There is no significant difference in the image quality of group A and B(Z=-1.75,P=0.08);The average CTDIvol value of group A and B was 1.82mGy、4.50 mGy.The CTDIvol value of group A was less than group B(t=-32.5,P=0.00).The CTDIvol value of group A was decreased by 59.56%than group B.The average DLP value of group A and B was 38.41mGy、82.74mGy/cm.The average DLP value of group A and B was 38.41mGy、82.74 mGy.The DLP value of group A was less than group B(t=-37.94,P=0.00).The DLPl value of group A was decreased by 53.58%than group B.The scanning time of group A(0.27s)was shorter than group B(2.60s)(t=41.00,P=0.00).The scanning time of group A(0.27s)was less than group B(2.60s)(t=41.34,P=0.00).The scanning time of group A was accounted for only 10.38% of group B.Conclusion The high-pitch scan mode of dual-source computed tomography has higher scanning speed,lower radiation dose in the chest,there is important value in the loe-dose scanning of children's chest.